Large-scale deployment of 3G networks has greatly promoted use of data services. Charging and control for over-the-top (Over The Top, OTT) applications is seen as an important technical approach to improving accuracy of charging and control for operator network traffic, enhancing user experience, and deriving more revenue from every bit of traffic.
Current charging modes include online charging and offline charging. Online charging is mainly as follows: Before a user uses a service, a credit (that is, the number of resources that may be used by the service) is granted; a network element controls use of the service according to the credit granted by an online charging system (Online Charging System, OCS); and when the user runs out of the granted credit, the network element requests the OCS to grant a new credit, and further, the user is charged in real time according to usage of the service.
Policy and charging control (Policy and Charging Control, PCC) is a policy and charging control mechanism defined by the 3rd Generation Partnership Project (3rd Generation Partnership Project, 3GPP). In the mechanism, a PCRF entity makes a policy decision (Policy Decision) to generate a data flow charging policy and control policy for a PCEF entity and generate application detection and application control policies for a TDF entity; then the PCRF entity delivers an application activation control policy to the TDF entity for installation, and delivers the flow control and charging policies to the PCEF entity for installation; according to the charging policy delivered by the PCRF entity, the PCEF entity initiates an application credit quota request, namely, a credit control request (Credit Control Request, CCR) message, to the OCS, and the OCS grants a quota, and returns the granted credit to the PCEF entity. In this technology, application charging information is collected based on 5-tuple information of an Internet Protocol (Internet Protocol, IP) packet, where the 5-tuple information includes a source IP address, a source port number, a destination IP address, a destination port number, and protocol information of the IP packet. There are many OTT application providers on the Internet, and the quantity of these providers is constantly changing, and consequently, an operator cannot provide an IP layer identification rule for every OTT application. Further, some different OTT applications use a same IP address. For example, different applications of a same provider use a same external IP address and they are distinguished by internal paths of a server. In this case, an application cannot be identified merely by an IP layer, and an operator cannot perform application-based charging for an OTT application by means of IP layer identification.